Evolutionary anthropologist, biologist and psychologist
Robin Dunbar is most famous for comparing primate brain mass and troupe size
to find the social limits imposed by the human brain. Dunbar’s number
(about 150) can be seen limiting the populations of indigenous tribes, army
units, corporate offices and other social groups worldwide. Ian Murphy called
Dunbar at his office at the Institute of Cognitive and Evolutionary Anthropology
at the University of Oxford.

Thanks for taking the time. Let’s start with language.
Your idea of language is that it’s—what is your idea of language?

Um…
I guess it’s that language primarily serves a social function, rather
than—

Communication.

Yes…

It’s not always about communicating?

Well, it is about communication, but the traditional view of
language is that—what I call the Einstein and Shakespeare idea of language.
It’s very highfalutin and it’s all about how you make things and,
you know, how to arrange going hunting and things like that—technical
information exchange. And I guess my view is simply that that is secondary to
the primary function, which has to do with social bonding.

Yeah, you’ve drawn the parallel to grooming.

Yes. So it replaces—it doesn’t replace grooming,
it adds to grooming in a very efficient way in humans, because we simply wouldn’t
have enough time to bond our social groups by grooming in the way monkeys and
apes do.

And we have showers.

Yes. We do lots of other things that also have the same effect
as grooming. That is to say the reason grooming seems to work is that it triggers
an endorphin release, so you get this sort of light opiate high when you—we
still do when you’re sort of cuddled and petted by somebody it produces
the same effect. But we’ve also discovered, if you like, other ways to
produce that effect that doesn’t require direct physical contact. And
one of them is laughter, so joking. You can therefore get lots of people bonded
at the same time. Whereas the problem with grooming is that it’s a one-on-one
activity; you can only do it to one person at a time. But by getting people
to laugh, you can get a whole group kind of jelled together. Religious rituals
are very good at having the same effect—and singing and dancing.

What do you think repetition has to do with religious ritual?

There’s something peculiar about repetitive movements,
which seems to be particularly good at triggering trance states. And these trance
states seem to be tied up with the release of these neurochemicals that are
deeply involved in bonding—including both endorphins, the brain’s
own painkiller, and also oxytocin—the so called love drug.

Are we the only species that does that?

On the scale that we do, I think we are. Primates do it using—these
same mechanisms are involved. Both these neurochemicals are heavily involved
in social bonding in all mammals in fact, but it’s really confined to
the few species which have pair-bonded mating systems. But primates are different
in that they have more intensely deep-bonded groups where individuals have these
pair-bond-like relationships with several individuals, and they’re not
necessarily reproductive. What we’ve done is taken a kind of pair-bond
mating relationship and generalized it to create a class of friends, in relationships
which are not sexual in that sense, but are intensely social and create this
same sense of, if you like, obligation and so on that you get in pair-bonded
relationships in other species.

So, while a group of people are creating their social bond,
are they also excluding the other?

Um, that is probably almost inevitable, so I think yes. The
lot of these, these mechanisms are designed to create intensely well-bonded
communities. But in a traditional kind of context, in an evolutionary context,
that is, in much smaller scale societies than—of course we are way beyond
small scale societies! [Laughs]

You’re probably best known for your number of approximately
150, which is uh—

That’s a small scale society, yes! But the interesting
thing is: that these, these mechanisms very easily capture, um, on a grander
scale, so that comedians, but also preachers can appeal to very large number
of individuals, far beyond 150.

Uh huh…

What seems to happen is that these kind of people, preachers
ands comedians, kind of share qualities in terms of their performance, their
ability to—I mean, if you think of a kind of classic Baptist-type, you
know, charismatic-type, church service where there are lots of, you know, ‘hallelujahs’
and ‘yes brother,’ and all this kind of stuff, you know, the way
the preacher works the audience and builds them up into this sort of state of
intense excitement is very, very similar to the way a comedian works the audience.
And it probably requires the same kinds of social skills to be able to do it.
Hopefully, the purpose is very different, but it’s exploiting the same
kind of bonding mechanism, which kind of makes us feel, you know, very happy
with the world and with everybody—‘We’re doing it!’
when we come out of Ives’ fifth, or the church, according to which way
you’ve gone.

So, the means are different, but the end is the same.

Well, the end that it creates is a sense of belonging to a
community. And I think the point is then that you can use that, in principle,
to create a very large scale community, on a bigger scale, in the way big religions
do, you know, in that they create this sense of belonging. I don’t think
comedians don’t work quite so well at that. There’s seems to be
something kind of slightly peculiar about religion that really makes you feel
that if you’re part of this small community, then another community
down the road which signs up to the same set of beliefs, belongs to the same
church, you know, is also part of your extended community and therefore you
know you should be nice to them. It offers the opportunity of political power
to create enormous…social groupings, in effect, far beyond the level
of tradition societies of 150.

Do you think that this kind of inclusion and exclusion that’s
caused by social binding, like, that results in, you know, racism, religious
spats or tribalism—do you think it’s endemic to the human condition?

I think it probably is. I mean this goes back. If you look
at all tradition societies—all the hunter gatherer societies—they
all have this distinction between us and them. And indeed it’s in the
very words they use. The words, most of these traditional societies—which
are pretty much now confined to sort of the Amazon, South American jungles and
bits of Africa and bits of Southeast Asia——the word nearly all of
them use for themselves doesn’t say, like, ‘We are Americans’
or ‘We are British’ or whatever, it just says we are human—human.
And the big distinction is between us and our community, who speak the same
language, and them out there, who don’t count as human. And it doesn’t
make too much difference, as it happens, if they belong to a different human
group, as it were, or if indeed they’re animals. It’s clearly—hunter
gatherers of that kind are not confused! [Laughs] They don’t confuse
zebras with, you know, members of another tribe in a kind of ontological sense.
You know: ‘Those people over there, in that other tribe are human in the
sense that we are, but they don’t belong to our group and therefore they
don’t count as human!’ And this is a very, very—almost universal
feature of human society. And I think it goes back to the fact that, like all
primates, our social, you know—our kind of evolutionary success hinges
on solving the problem of survival and successful reproduction communally. We
live in an implicit social contract. And to make an implicit—so you gain
disproportionally by collaborating in the processes of successful survival and
reproduction, in a way which is dependent on individuals being very committed
to each other. But you can’t do that with an unlimited number of individuals
in the natural state, as it were. It only works up to a certain point, and that’s
why you get these limits on group sizes. And we’re kind of stuck with
that psychology, if you like. I mean, it’s one argument for the fact that,
you know, we have a stone-aged mind and a space-aged body. Here we are, the
world has changed! What is it, 305 million in the US as of today? Going up to
450 by the middle of the century, I heard the predictions this morning.

That’s just not sustainable, is it?

[Hearty laugh] Well, you know, I mean, that is another
issue, I mean, whether it’s sustainable or not. Let’s be charitable
and say it is. It’s perfectly clear that you can maintain some sort of
social cohesion—even on something at that scale, in that, you know, all
you guys, you know, sign up to certain kinds of principles and beliefs, you
know, as laid out in the Constitution and so on. And that’s kind of reinforced
every morning in school with the kids with the…uh…the…what’s
the thing with the flag and all this kind of stuff. So, you can create a sense
of belonging to a community on that kind of enormous scale, but it’s never
going to have the same feel to it.

It’s a more tenuous bond—

Well, it is. It’s never going to be on the scale that
you’ll get in a small rural community in the Appalachians or Quintana
or somewhere, where people’s roots go back many generations in that community
and many people are kind of interrelated with each other. That sense of small
scale community can be very, very deep and very committed. You know, if you
threaten one of my second cousins twice-removed, you’re threatening me.
Whereas, you know, on the east coast you may look askance at what happens in
California. “Let ‘em!” If California falls off the edge of
the continent, who cares?

Yeah, Lex Luthor had it right.

But nonetheless, you know, you see it in the context of war
and stuff, you know, if there’s a national atmosphere, then people kind
of pull together. They will never pull together in the way a small community
will pull together. But it’s still there—this sort of aegis. And
you can whip it up, you know, by exploiting these same sorts of psychological
mechanisms that create bonding in small communities. They can be whipped up
on the large scale, as is clear from many, many examples. I guess the Nazis
onwards and backward, really.

US society is still rather fractured, though…

Of course, because it’s so big! [Chuckling]

Yes. That said, how do you think this fractured tribalism
will factor into the upcoming US elections?

Yeah, that’s kind of really interesting, isn’t
it? In some sense the, you know, the way national level politics works is kind
of a…law unto itself, and often doesn’t necessarily bear any relationship
to what the communities are interested in. You know, there are small factions
kind of that drive it. And there are all sorts of other strange effects which
influence the way people vote, so people’s perception of the physical
traits of the candidates has a huge effect. Almost every US president elected
in the last century was the taller of the two candidates. And my colleagues
have looked at the facial symmetry of US presidents over the last century, and
again, the candidate that was elected had the more symmetrical face of the two.

That’s definitely not John McCain.

Ha!
Well, it starts to make you wonder. I mean, in fact, on the facial symmetry
stuff the predictions are so good that they—they were able to predict
the UK, the last UK election, the voting split between left and right parties
within half a percentage point.

Damn!

It seems to be extraordinary. Well, you know, you kind of go:
‘Democracy? What is this stuff?’ I do think there’s an issue
about—that comes out of all this—about the kind of integration of
society on the large scale, when you have these huge, you know, monolithic structures
that we have now. Obviously, we’re trying to create that in Europe with
the European Union. But, you know, sort of—you’re going to end up
with a kind of, not quite dysfunctional, but, you know, these sort of stresses
and strains within these very large units that are ultimately going to overwhelm
them, unless we can find a way to kind of neutralize them. And I cannot see
a way of doing that, short of something like, sort of, a mass religious experience.
Religion is very weird stuff. Whether you believe in it or not.

I believe religion exists.

You know, it seems to have this hold on people. There’s
something odd about the kind of spirit world or whatever you want to call it
that somehow fires people’s imaginations. Now, it’s irrelevant whether
it’s actually true or not. It just seems to be part of our psychology,
and I think it goes back to the nature of ancestral religions in these small
scale societies and how they kind of evolved right at the early beginnings.
These mechanisms seem to be extremely powerful. They seem to be able to capture
the sense of people, you know, and create this sense of community and commitment
to the grand project. Somehow it creates—and I think the way you do it,
in my view, for these big nation-states that we have now, is that you create
a grand project for the nation-states. So you ask, what is the US’s grand
project?

So, we’re looking for a kind of new New Deal—

Ha! Once you’ve got one—I kind of think that in
the 19th century, Britain’s was The Empire, and that created
this sense of purpose in life. This is what we’re doing, you know, this
is why we’re doing something that’s good. And so, people then pull
together and they go out and sort of commit themselves to this big project.

Don’t you think we’re going to have
to do something like that in regards to the environment?

That’s an interesting question, actually, as to whether,
because clearly the environment is a big, big serious issue. Um, you know, we’re
heading for deep shit.

Yeah, yeah. I mean, you need something like 500 parts per
million of carbon in the atmosphere to basically bake the planet, and we’re
at like 300 now, and it’s just going through the roof—

Right.

And China recently surpassed the US in emissions. It’s
just not good. I’m not optimistic.

The question then is: Is the environment a big enough project,
as it were, to have this effect? I mean, clearly it does with some people—the
environmentalist lobby. They have that kind of missionary zeal about them. But
is it a big enough missionary zeal, as it were, to virtually draw in everybody
to create this sense of single purpose for the country as a whole?

Can we be like that as a species without having a kind of
hive-mind—a bug-like existence?

Well, my problem with that is really that I think these neurohormone
effects are actually creating that hive-mind kind of thing. But it’s doing
it on a scale which is only in the region of 150. And as you go beyond 150 into
the successive layers out beyond that, the effect becomes smaller and smaller
and smaller very rapidly. And it just doesn’t have that kind of hive-mind
effect. I think the problem in the end is, with all primates, is one reason
they’ve got a big brain is to allow them to fine tune their behavior,
so that you’re constantly engaged in this kind of balancing act between
doing what is good in the communal sense, because you know in the long run you’ll
benefit from that, and also doing what is in your own selfish interest right
here and now. So there’s this constant trade off between short term and
long term benefits. And that always is the problem. This is the free rider effect
and it’s what destabilizes these communal effects. The hive effect, as
you get in bees, for example, everybody is committed to the big project because
they’re unable to step back from it and say, “Hmm, I could do better
for myself if I go this way and trade off everybody else’s generosity.”
And our problem is we can do that, and therefore we have this temptation to
constantly undermine the social contract. And, you know, our problem, as I see
it anyway, is how to get the balance between those two right. Because in some
sense progress depends on individuals being able to step back and say, “Hey
maybe there’s another way of doing it.” If you don’t have
that ability you don’t get science, you don’t get—I suppose
you get literature and all the rest of it that’s part of human culture,
as it were. But you don’t have that ability to say, “Uh-oh, there’s
a problem here, let’s find another way of doing it,” because the
hive effect will just have you in a rut.

Do you think that, we’ll eventually merge with silicon-based
life—and do a cool sort of cyborg thing?

[Giggles.]It’s an interesting question, isn’t it? There is an issue about
what constrains the structures of our relationships, so, you know, is the constraint
of the number of individuals you can have in your social network, this sort
of 150, as it were, or a time constraint? In order to know people well enough
to be able to work in this way, you have to spend time with them—socially
that is. Or is it a purely cognitive constraint, because you know, your brain
just isn’t big enough to hold all the information and manipulate all the
information about each individual for more than, let’s say, 150 individuals.
Now, if the second is the real problem, it’s a cognitive constraint, a
memory constraint partly, then you know an implanted silicon chip, which allowed
you to call up info on more individuals, might cut through that and allow you
to have a bigger circle of friends. If it’s a time constraint, it’s
not going to help at all. For a time constraint, maybe a cell phone would cut
through that, because you can reach more people more quickly, and therefore
maintain—and things like Facebook and Myspace, the networking cites, might
allow you to communicate with more people individually, because otherwise the
problem is, you’re back down to face-to-face things, you know, sitting
down and having a beer together. And there’s a limit to how much time,
you know, you can afford to spend, ah…

Yeah. Is that a hint?

Well, he-he-he! Well, here’s an interesting question,
which is seriously concerning, not concerning, but involving the kind of mobile
technology industry. Because, you know, it may be that having a cell phone or
SMS, or what have you, is a way to maintain larger networks of people. I’m
not entirely convinced, but I think it’s actually quite good for servicing
relationships—

And giving you brain cancer.

That’s a disadvantage.

Yeah.

There’s a key rule in biology: Namely, nothing comes
for free. There’s no such thing as a free lunch in real life. Anything
you do, there’s always a cost somewhere. So that may be the cost that
offsets the benefits. But I actually think the problem is that you cannot maintain
silicon relationships with people. Relationships come actually through direct
physical intimacy and contact, as it were. And that’s what in the end
limits how many people you can have in your social circle.

But on Myspace I have like 3,000 friends.

Sure.

We’re all really close.

That is the question: How close are they in reality? The work
that we and others have done suggest that most people’s Facebook and Myspace
networks mirror quite closely their everyday social relationships. And then
you’ve got a few people who have very large numbers of individuals. It’s
clear that people are very, I mean, some people are just better at maintaining
large numbers of relationships anyway. They can go above 150, easily. Some people
are poorer than that, maybe they can only handle 100. So that’s the natural
range of variation. But also, what Myspace lends itself to is having very large
numbers of people signed up there, which are kind of undifferentiated in terms
of the quality of the relationship. If you ask people to—of both parties—to
specify the quality of the relationship you‘ll find that they aren’t
equal. Because what you have to remember is that this number 150 is simply one
in a series of circles. So if you think about it in this way, you’re sitting
in the center of a series of expanding circles of friendship or acquaintanceship
with a very small inner core of about 5 best friends, and then there’s
a sort of layer outside that which include about 15 people, and another layer
outside that of about 50, then you’ve got your 150. As you go down through
those layers, the quality of the relationships is declining, but it seems 150
marks a real drop off. Now, there’s at least two other layers we know
about beyond that, one at about 500 and one at about 1500. There are suggestions
for layers at about 5000 out beyond that, too.

What’s up with that?

You kind of know these people, and you have some sort of relationship
with them, in these outer layers, but they’re not deeply personal relationships.
They’re kind of acquaintances and people you know for professional reasons
that, you know, you want to have or maintain contact purely for professional
reasons. But you probably wouldn’t be too bothered if they passed by your
town to have a—you’d be happy to have a beer Friday after work,
but if they came along on Saturday they’d be a nuisance.

At Oxford you studied with Richard Dawkins, is that correct?

I was an undergraduate here, when he first started lecturing,
so I did have lectures from him, but I wouldn’t say I studied with him
in that he physically taught me, but he certainly lectured to me.

What do you think about memes?

Oh, they’re fine. I don’t have a big problem with
them. It’s just a useful handle for referring—I mean, the problem
is it’s clear that there’s stuff that gets passed on from one individual
to another which is not genetic, right, which is cultural. We need a word just
to refer to that, and memes, to be honest, is as good as anything. Any problem
comes when people get to exercised about the exact relationship between memes
and genes. But in terms of stuff that you learn, there’s lot of parallels
with the way genetics works. You don’t want to get too bogged down in
the details, because that’s when you start to get silly objections to
it. It’s just the transmission of stuff you learn. That’s good enough,
that’s fine. It allows us to at least know what we’re talking about.

I’m just fascinated by the ideas of people like Daniel
Dennett, who talk about memes and genes, and how these things both replicate
in a Darwinian sense—and it’s basically substrate neutral, is the
way he puts it.

Yeah, sure. And I think this is true. It’s true that
memes operate in a memetic universe that is quite separate from the genetic
universe, where the genes operate, and sometimes the relationship between the
two can be quite loose. Things can evolve in this cultural universe in ways
that are disadvantageous to the genes and the bodies transmitting the meme…to
be honest we’re still a long way from really understanding all the ins
and outs of how these things function, but as a principle I don’t really
have a problem with it.

Professor Dunbar is the director of the British
Academy Centenary Research Project "From Lucy to Language: The
Archaeology of the Social Brain".